Princess Elizabeth’s Spy by Susan Elia MacNeal

I met the endearing Maggie Hope in MacNeal’s Mr. Churchill’s Secretary this past summer, and could not wait for Princess Elizabeth’s Spy to come out.  Now Maggie has completed her MI5 training (or as much as she can:  Maggie is an expert code breaker but physically can’t meet the rigorous demands) and has gone under cover as a math tutor for Princess Elizabeth at Windsor Castle, though her real purpose is to protect the princesses and keep the former King Edward VIII from returning to the thrown.   Maggie is drawn into a huge conspiracy at the castle when a lady in waiting riding with the princesses is killed, and no one is quite sure who the intended target was.  This history mystery is a perfectly enjoyable weekend read and comes highly recommended by this book barista!